Hydraulic back rest



A. F. STEINER HYDRAULIC BACK REST Filed Oct. 22, 1926 2 Sheets-Sheet l QM E www mm Oct. 3o, 192s. l 1,689,409

AP;STENER HYDRAULIC BACK REST 2 Sheets-Sheet 2 Filed t. 22, 1926 HVVENTOR. limo@ Pemez'.

BY n

\ ATT NEX Patented Oct. 3Q, 1928.

UNITED STATES PATENT OFFICE.

AMOS P. STEINER, OF WAYNESBORO, PENNSYLVANIA, ASSIGNOR TO LANDIS TOOL COMPANY, OF WAYNESBORO, PENNSYLVANIA, A CORPORATION 0F PENNSYLVANIA.

HYDRAULIC BACK REST.

Application ledvOctober 22, 1926. Serial No. 143,482.

My said invention relates to a hydraulic back rcst for crank-shaft grinding machines. Heretofore it has been necessary for the operator toy occasionally adjust the back rest as the grinding progressed whereas my device` when once adj usted. keeps a constant tension or pressure on the work and ceases to exert pressure when the work has been ground to the proper size. Another object of my device is to provide means for holding the back rest in a retracted position. A further object is to provide means for limiting the inward movement of the back rest. A still further obj ect is to support two cranks at a time with one device.

Referring to the accompanying drawings which are made a part hereof and on which similar reference characters indicate similar parts, I

Figure 1 is a side elevation of my invention,

Figure 2, a front elevation thereof with parts broken away for clearer illustration,

Figure 3, a fragmentary plan view of the. front end of the device,

Figure 4, a detail section on the line l4--4 of Figure 3, and s Figure 5, a similar view on the line 5-5 of Figure 3.

In the drawings the numeral 10 denotes a carriage or swivel table to which the back rest 11 is secured by clamping bolts 12 which allow for lateral adjustment. The work, in this in stance, is a crankshaft 13 on which two crank pins are ground at a time by two grinding wheels 14 as shown in Figure 2. The back rest 11 consists of a casting having formedn therein a pair of parallel cylinders each lined with a bushing 15 and closed at one end with a cylinder head 16. A piston 17 operates within each cylinder on piston rods 18 which eX- tend beyond each end of the cylinder. The inner end of each rod 18 is slotted to form jaws 19 adapted to receive a bearing block 20 conlined therein by means of a bolt 21 which passes through the jaws 19. As the pistonrods are designed to move in unison, they are con` nected adjacent their outer ends by a yoke 22 which also is used as a latch plate, to be more fully described later. The outer ends of the rods 18 are threaded to rece-ive adjusting nuts 23 which limit the inward movement of the rods and bearing' blocks 20. The cylinder heads 16 are cut away at 24 to receive the yoke 22. Lugs 25 are left by the cut-away portion and form stops for the adjusting nuts 23. A

spring 26 surrounds each piston rod 18 and acts to force the pistons 17 and their associated parts away from the work when the hydraulic pressure is released. This device is primarily intended to be used in conjunction with a hydraulic crank clamping fixture described in an application of Amos P. Steiner, Paul Stoner, and Charles P. Harrison, Ser. No. 126,583, for crank grinding machines, filed August 2, 1926, and both devices are located in the same pressure line so that when pressure is exerted on the clamps (not shown) it also acts on the pistons 17 through a pipe 27 which enters one of the cylinders, passes through a port 28 formed in the casting and communicates with the other cylinder, so that they both receive pressure at the same time. When the piece of work has been ground to size and the pressure has been released, the springs 26 force the pistons towards the heads 16 thereby withdrawing the blocks from the work and also forcing the pressure iuid back through the pipes 27 and 34 and its connec- .tions to the storage tank.

In order to hold the blocks 2O out of contact with the work until the rough surface has been trued out, a gravity latch 29 is provided which is pivoted to the casting 11 and has rollers 30 mounted to drop behind the latch plate 22 and prevent the iiuid pressure from advancing the various parts. After the rough surface has been removed, the operator simply lifts the latch from the latch plate and allows the blocks to engage the work.

The back rest as described may be used as a unit. However, should the occasion demand more than one unit, I have provided a port 31 which is normally closed by a plug 32 which may be removed to connect another back rest thereto by a separate pipe connection.

When the device is used on a plain machine for grinding straight shafting the latch 29 is unnecessary as the flow of pressure fluid to the cylinders is controlled by a three-way valve 33 which in one position allows the fluid to flow from the pressure line 27 to the cylinders and when in another position, allows the pressure fiuid to flow from the cylinders through the discharge pipe 34.

Mounted on a suitable slide-way formed on the top of the base of the back rest 11 is a holder 50 in which a shank 51 of a diamonding tool 52 is mounted. By 'loosening the bolt which holds the holder 50 to the backso far as keeping the face of the grinding Wheel in true form is concerned.

It will bel obvious to those skilled in the art, that various changes may be made in my device Without departing from the spirit of the invention, and therefore I do not limit myself to what is shown in the drawing` and described in the specification, but only as indicated in the appended claims.

Having thus fully described my said invention, What I claim as new and desire to secure by Letters Patent, is:

l. A hydraulic back rest comprising a casting, multiple cylinders in said casting, a piston and piston rod in each cylinder, said rod extending beyond the 4ends of the cylinder, a bearing-block on one end of each rod, an adjusting nut on the opposite end of each rod,

hydraulic means to force said rods in the block on one end of said rod and a nut on the opposite end thereof, hydraulic means to force said ro'd in the direction of the vvork, resilient means tending to force said rod in the opposite direction and a latch havingir a roller adapted to be placed between the nut and the cylinder vend to retain the partsv in the last mentioned position, substantially as set forth.

vIn Witness whereof, I-have hereunto set my hand at Waynesboro, Pennsylvania, this 18th day of October, A. D. nineteen hundred and twenty-six. i

AMos Pf STEINER. 

